Energy harvesters have enabled widespread utilization of ultra-low-power devices that operate solely based on the energy harvested from the environment. Due to the unpredictable nature of harvested energy, these devices experience frequent power outages. They resume execution after a power loss by utilizing intermittent computing techniques and non-volatile memory. In embedded devices, intermittent computing refers to a class of computing that stores a snapshot of the system and application state, as a checkpoint, in non-volatile memory, which is used to restore the system and application state in case of power loss. Although non-volatile memory provides tolerance against power failures, they introduce new vulnerabilities to the data stored in them. Sensitive data, stored in a checkpoint, is available to an attacker after a power loss, and the state-of-the-art intermittent computing techniques fail to consider the security of checkpoints. In this paper, we utilize the vulnerabilities introduced by the intermittent computing techniques to enable various implementation attacks. For this study, we focus on TI’s Compute Through Power Loss utility as an example of the state-of-the-art intermittent computing solution. First, we analyze the security, or lack thereof, of checkpoints in the latest intermittent computing techniques. Then, we attack the checkpoints and locate sensitive data in non-volatile memory. Finally, we attack AES using this information to extract the secret key. To the best of our knowledge, this work presents the first systematic analysis of the seriousness of security threats present in the field of intermittent computing.
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Modal Crash Types for Intermittent Computing
Intermittent computing is gaining traction in application domains such as Energy Harvesting Devices (EHDs) that experience arbitrary power failures during program execution. To make progress, programs require system support to checkpoint state and re-execute after power failure by restoring the last saved state. This re-execution should be correct, i.e., simulated by a continuously-powered execution. We study the logical underpinning of intermittent computing and model checkpoint, crash, restore, and re-execution operations as computation on Crash types. We draw inspiration from adjoint logic and define Crash types by introducing two adjoint modality operators to model persistent and transient memory values of partial (re-)executions and the transitions between them caused by checkpoints and restoration. We define a Crash type system for a core calculus. We prove the correctness of intermittent systems by defining a novel logical relation for Crash types.
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- Award ID(s):
- 2007998
- NSF-PAR ID:
- 10426409
- Date Published:
- Journal Name:
- European Symposium on Programming
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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